When a cable carrying an RF signal, such as a cable television signal, is disconnected from a television set or a cable box, the RF signal is emitted into the environment unless the connector is properly terminated. If a cable provider is aware of a non-terminated connector, its personnel can attach a terminator to the connector. In the case of a coaxial cable connector, the terminator is attached to the end of the connector to short the center conductor to an outer circumferential conductor with a 75 ohm resistance.
As the number of non-terminated emitting connectors increases, the power output from the cable plant must be increased to compensate for the lost power from non-terminated connectors. The signals emitted in the atmosphere can also cause interference with other vital communications sources, such as airport traffic control. If the problem becomes particularly severe, a cable provider must send out a "sniffer truck" to detect RF signals in the environment and order to locate the source of leakage.
At a household, such leakage can be caused in a number of different ways. For example, a consumer who is receiving a cable television signal might disconnect the cable from the cable box to the television temporarily if the television is being repaired. Another possibility is that the customer might attach a splitter to the cable box to run a separate cable to a video cassette recorder. Later, the consumer may stop using the recorder, but not remove the splitter. Some people, when they move have been known to is remove the cable all the way to a ground fixture outside the house, thus leaving open the possibility that the signal could be emitted from the ground fixture. It is also increasingly common for cable fixtures to be built into new homes or in remodeled rooms. Fixtures are positioned in the wall similar to telephone fixtures for convenient attachment. If the signal is not properly terminated at each fixture, a signal can be emitted out of any non-terminating fixture.